The professor explained that Staphylococcus was a common bacteria on all modes of transport in the capital. It can cause skin problems such as puss-filled boils as well as serious infections in the blood, lungs and heart.

Dr Matewele added: “Bacteria from rodents like rats and mice were also found upon tube lines, along with bacteria found in faeces and bacteria from sewage. These can cause water infections or skin infections like abscesses if you come into contact with them.”

Freedom of Information requests revealed earlier this year that the only Tube lines where seats are washed are the Bakerloo, Victoria and Central, whereas most are simply brushed.

However, it was also revealed that each carriage is cleaned every night.

Ashley Peters, Managing Director at Staveley Head, said it made “good business sense” for cab drivers to clean the inside and outside of their vehicles regularly.

He added: “We’d also obviously recommend that passengers riding the tube lines and buses practice good hygiene and regularly use hand sanitiser.”

Jill Collis, Director of Health, Safety and Environment for TfL, said: “The Tube is an extremely safe environment and our trains and stations are professionally cleaned throughout the day and night.

“There is no cause for customers to worry about bacteria on the Tube or do anything different in terms of hygiene than they would in other public places.”